The shoring or bracing of cargo in transportation containers by means of cargo shoring beams or bars is extensively employed in the trucking, railroad and other transportation industries. Truckers, for example, having a partial truckload will use a cargo shoring bar to span across between the inside walls of the truck trailer immediately adjacent to and abutting the partial load. Several bars are typically employed and secure the load against shifting during transit.
Cargo shoring devices are constructed with a foot assembly on each end thereof which either frictionally engages the cargo container wall or interfits or hooks into a track or series of openings provided in the wall. The track-type cargo shoring devices have the disadvantage of requiring a wall-mounted structure, which inherently places certain limitations on the ability to position the shoring bar. There are other disadvantages to the track-type shoring device. Another common approach to shoring or bracing cargo is to employ a cargo bracing device which is extensible between opposed walls of the cargo container and formed to frictionally engage the walls and thereby hold the carbo bracing device in place. Such extensible, friction-based, cargo-bracing devices can be positioned virtually anywhere in the cargo container, including positioning so as to brace between the floor and ceiling.
Typical of cargo-bracing devices which include an extensible element that is advanced by relative rotation of interengaged threaded elements are the devices disclosed in U.S. Pat. Nos. 1,951,660; 3,171,627; 3,329,388 and 3,880,394. These apparatus are well suited for some applications but can be difficult for the operator to manipulate in other applications. The device of U.S. Pat. No. 3,049,328 has been widely used in industry and includes a bar having a fixed foot assembly on one end and a moveable foot assembly on the other. The bar is positioned between opposed walls of the cargo container and a lever used to extend the moveable end of the bar outwardly against the walls. The walls will flex somewhat under the axial force generated by extension of the bar, and the bar will be frictionally bound between the walls in a snug position proximate the cargo. The assembly includes a latch so as to hold the lever and the extensible portion of the bar in the extended position.
While cargo shoring devices constructed in accordance with U.S. Pat. No. 3,049,328 have been found to have many substantial advantages, certain disadvantages have been encountered. As will be appreciated, it is essential that a cargo shoring bar be positioned as closely to the cargo as possible, and preferably abutting the same. Such cargo shoring bars are typically about 71/2 feet (2.3 meters) long and weigh about 10 to 15 lbs. (4.5 to 7.4 kilograms). Very often, positioning of the bar against the load also requires that the load be held back during placement of the bar. Moreover, when the bar is to be removed, it is not unusual for the load to have shifted in a manner which requires it to be supported during removal of the bar. Manipulation of cargo shoring bars during placement and removal of the same, therefore, poses substantial problems. It is preferable, therefore, to be able to place and remove the shoring device with one hand so that the other hand can be used to support the load during the installation and removal processes. Since the opposed walls of a cargo container act as a large spring, unlatching cargo bars constructed as shown in U.S. Pat. No. 3,049,328 is a two-handed process if one is to avoid snapping back of the lever and dropping of the bar to the floor of the container.
As will be appreciated, cargo shoring beams or bars can, over a period of time, become bent or damaged by shifting loads and the like to a point which is beyond their repair by simply attempting to straighten out the bar. In most cases, such damage requires that the bar be discarded, which can be a significant economic loss when considering the number of cargo shoring bars in use and periodically damaged beyond repair.
In addition to the use of bar- or beam-type cargo shoring devices, there is a need for cargo shoring devices which are partitions or moveable walls that can be mounted in a cargo container, particularly to shore up relatively small articles. For cargo shoring partitions, the problems of manipulation of the partition during placement are even greater than for bars, and there similarly is a substantial need to be able to accommodate cargo containers of varying widths and heights. As is the case with cargo shoring bars, cargo shoring partitions will periodically become damaged beyond repair, and they are preferably formed so that the economic loss when such damage occurs is minimized.